view tests/test-merge10.t @ 18234:a55b06885cda

branchmap: allow to use cache of subset

Filtered repository are *subset* of unfiltered repository. This means that a
filtered branchmap could be use to compute the unfiltered version.

And filtered version happen to be subset of each other:
- "all() - unserved()" is a subset of "all() - hidden()"
- "all() - hidden()" is a subset of "all()"

This means that branchmap with "unfiltered" filter can be used as a base for
"hidden" branchmap that itself could be used as a base for unfiltered
branchmap.

   unserved < hidden < None

This changeset implements this mechanism. If the on disk branchcache is not valid
we use the branchcache of the nearest subset as base instead of computing it from
scratch. Such fallback can be cascaded multiple time is necessary.

Note that both "hidden" and "unserved" set are a bit volatile. We will add more
stable filtering in next changesets.

This changeset enables collaboration between no filtering and "unserved"
filtering. Fixing performance regression introduced by 47f00b0de337

Test for changeset 9fe267f77f56ff127cf7e65dc15dd9de71ce8ceb
(merge correctly when all the files in a directory are moved
but then local changes are added in the same directory)

  $ hg init a
  $ cd a
  $ mkdir -p testdir
  $ echo a > testdir/a
  $ hg add testdir/a
  $ hg commit -m a
  $ cd ..

  $ hg clone a b
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd a
  $ echo alpha > testdir/a
  $ hg commit -m remote-change
  $ cd ..

  $ cd b
  $ mkdir testdir/subdir
  $ hg mv testdir/a testdir/subdir/a
  $ hg commit -m move
  $ mkdir newdir
  $ echo beta > newdir/beta
  $ hg add newdir/beta
  $ hg commit -m local-addition
  $ hg pull ../a
  pulling from ../a
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files (+1 heads)
  (run 'hg heads' to see heads, 'hg merge' to merge)
  $ hg up -C 2
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge
  merging testdir/subdir/a and testdir/a to testdir/subdir/a
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg stat
  M testdir/subdir/a
  $ hg diff --nodates
  diff -r bc21c9773bfa testdir/subdir/a
  --- a/testdir/subdir/a
  +++ b/testdir/subdir/a
  @@ -1,1 +1,1 @@
  -a
  +alpha

  $ cd ..